Equation
by Emma CS Me
Summary: Puck needs to believe that; that this is all Finn's revenge scenario, and not kind of what he's always wanted.


**A/N: **Written for this prompt on the **glee_kink_meme**: "Finn always pretended he didn't know what Puck's "pool cleaning" business entailed. Now, he calls him up in need of his services. Angry, bitter hate sex purely to humiliate Puck. Huge bonus points if Finn throws the money down afterwards a la moulin rouge and makes a snide comment about paying for his kid."

* * *

**Equation (Don't Eat Chlorine)**

Puck doesn't know what he's doing here.

When he saw Finn's name on the caller ID at three AM, he was like eighty-two percent sure he was dreaming, with a fifteen percent chance that Finn was just totally going to rip him a new one (which he kinda would have deserved, but not the point).

He didn't expect what he got, however. "Puck," Finn said on the phone, tone scarily flat and empty, and sounding more than a little drunk, "Need you to come over. Work for you."

And Puck followed, like a good little lapdog. He knew people said either he was always the second-string to Finn and always hanging on to the glory on the sides, or Finn was a dopey moron who'd trail after Puck and his personification of the adrenaline rush – which one depended on the people – but it was never like that, not really. Finn and Puck were just that, _Finn_ _and Puck_; neither one really worked without the other, even when they fucking hated it, and they'd both snap at their best friend's orders, no matter what.

Maybe that's something to do with why Puck fucked Quinn anyway; trying to prove he and Finn weren't actually conjoined or anything.

He winds up at Finn's door, shivering in the November weather. When Finn opens it, he's grimacing.

"You better have a fucking good reason for this, Hudson; I'm _cold_," Puck whines, apologetic smile playing on his lips, as if he just wants to pretend the whole thing never happened – he tried that at Sectionals and it didn't really work, but Finn called _him_, so it's worth trying again.

Finn rolls his eyes. "Come in," he grumbles, and Puck does so semi-slowly – he can't quite shake the feeling he's about to fall through a trapdoor into a pit of lava and venomous snakes (wouldn't the lava kill the snakes? Oh well, not the point).

The just stand there awkwardly for a few seconds. "So," Puck eventually says, "What's going on?"

Finn's face remains blank as he comes closer, circling around Puck threateningly – he kind of makes Puck think of Jaws. This isn't creepy at all. "Dude, what the fuck are you doing?"

Finn chuckles, low and dark and unlike anything Puck's ever heard from him before – which is confusing as hell, because it's _Finn_, and Puck's known him since they were like four and he doesn't understand how he could have missed anything by this point.

"Dude, you're freaking me out."

Finn goes still – good, that was making Puck dizzy – and leans in close to Puck's ear (that's less good). "Good," he whispers. "I've got work for you."

And with that, Finn gives him a rough, quick shove – Puck stumbles, and barely manages to manipulate his body so he lands on the couch and not the floor, giving himself concussion and dying. Can you die of concussion? Anyway. "Okay, you're kind of making me think of some kind of alien invasion. If you're still pissed about that Quinn thing, dude, just say so."

Finn smirks, and kneels down on the floor beside him. "'That Quinn thing'?" he echoes, rather obviously mocking Puck, which pisses him off. Finn's the dumb one and he's the smart one – well, not with school and shit, they both pretty epicly failed that – and this whole situation is whack. However, it's been like that for months (okay, years if he's being honest), so Puck really shouldn't be surprised.

"Dude–" Puck says as he struggles to get back up, but Finn grabs his forearm _hard_ and pushes him back down.

"Tell me about it, Puck," Finn says, staring him dead in the eye and still gripping his arm. Puck reckons that's gonna bruise like a bitch if Finn doesn't let go soon, but he doesn't really care (should he care?).

"...What?" Puck asks.

"Don't play dumb," Finn says, his voice losing a little of that creepy cool edge. "Tell me about it. Her. Everything. Tell me what was so fabulous about _my_ girlfriend's pussy that you just couldn't resist?"

Puck grimaces – he doesn't know how to answer. He still doesn't really know why he did it. Sure, Quinn was smoking hot, but so were plenty of the chicks he'd already gotten into, and they were a hell of a lot more experienced. Quinn, for all her wolf-in-sheep's-clothing attitude, was really just a fucking sheep, and all through it she made these little whimpers as if he'd hurt her, or scared her, and he just felt like the biggest piece of shit ever to exist. Afterward, she wouldn't look him in the eye, like he had defiled her – she whispered 'whore' under her breath, probably thinking he couldn't hear. He didn't even know which one of them she was referring to, but still, it kind of stung – if it was her, he felt bad for making her think that way about herself (what kind of nutjobs were the Fabrays anyway?). If it was him, it was an insult (possibly an accurate one, if he's being honest) and that always sucks.

Puck comes back to reality and realizes Finn is still staring at him, expecting an answer. "I don't... I don't know," he stammers out, half-expecting Finn to punch him again. He doesn't.

He just shrugs. "Whatever, it's not like I really should be surprised," he says. "I'm an idiot. My best friend's a whore, and I'm surprised at him fucking anything that moves?"

Puck flinches a little. "I'm not a whore," he says, even though, yeah, he kind of is. Not that Finn knows that.

Apparently. "Please – you think I didn't figure your 'pool cleaning' business out ages ago? We live in Ohio, Puck."

Well, fuck. "Yeah, but... you're an idiot. How were you meant to tell?"

Finn rolls his eyes. "Yeah, well, guess the moron is a pissed moron now."

Puck groans. "What do you _want_, dude? I'm sorry, okay? And I like never apologize."

"Well, that's sweet and all, but I don't forgive you," Finn says. His eyes wander. "I loved her so much," he whispers, more to himself than anything.

Puck's stomach drops. "Quinn or the baby?"

Finn shakes his head. "Doesn't matter."

"Then can I just go?" Puck says, resisting Finn's grip to get up, but Finn just shoves him down again.

"No. Like I said, I have work for you."

Occasionally, Puck is kind of an idiot, so he can't figure out what Finn means. "...Work? What kind of work?"

God, that doesn't sound pathetic. Finn rolls his eyes. "What kind of work do you normally do, Puck?"

Oh.

Fuck. No.

Puck leaps up then, defying the grip Finn still has – guess he's panicking. "Oh no, I don't know what the fuck you were thinking of, dude, but–"

Finn grabs his wrist, keeping him still again. Puck struggles, but Finn's bigger than him, stronger than him, and when Puck does so Finn just grips harder, and Puck considers the possibility of finger-shaped bruises on his wrist. "Come on, Puck," Finn says. "I know you. If this is all you're good for, let's give it a whirl."

Puck tries to breathe. "Okay, dude, this is all sorts of fucked up and I totally screwed you over, but... You know me, but I know you, and you've fucking lost it."

"I know," Finn admits. "Doesn't matter. Come _on_; if you're the Puckarilla 2000, ride of the century, why don't I get my turn? Let me at least know what everyone wants so damn much?"

Puck doesn't actually get the chance to reply before Finn cuts him off, pressing their lips together in a rough not-kiss. Finn's grip on his wrist tightens as he stabs his tongue forward – no finesse at all, and Puck thinks that kind of gives away his tough act, like he knows exactly what he's doing. He doesn't. Puck just stands there, not responding but not exactly resisting either – he parts his lips willingly, letting Finn's tongue dart around.

They separate after a few seconds, slight trail of spit snapping between them and landing on both their chins – _Ew_, thinks Puck. "Puck," Finn murmurs, and something in the aforementioned's stomach twists.

"What?" Puck asks, but he doesn't really care. Finn doesn't answer, and stares at him a little. "Look, dude, I screwed up..." he trails off, unsure how to finish.

"Like that's any surprise?" Finn replies, his words sounding a good deal less bitter now, but that doesn't make them feel any better. Puck begins to realize just how fucking _screwed_ he is.

"It should be," Puck replies, looking down. "To you at least."

And yeah, that's it. Puckzilla fucked everyone around him over at levels that could get him in with the Guinness Book of Records, but the thing was, Finn never _noticed_ that. Finn was an idiot, and Puck kind of liked (loved) that, because that actually made Finn the only person like, ever, who thought he was capable of doing anything good. Apart from sex. Puck is never going to admit this aloud, but yeah, he _needed_ that and he totally fucked himself over. Because the Quinn thing was so not worth any of this.

He. Is. So. Screwed.

Finn snorts, but then he looks... kind of sad. "You wanna hear a joke?" he asks. "It actually was."

"Thank god for that."

Puck suddenly realizes how close they are still standing – he can still see some saliva on Finn's lips – and Finn presses a hand to his eye, where he punched before, making Puck wince. That's going to be one kiss-ass black eye soon. Despite everything, that punch totally took him off-guard – he never expected Finn to do that; sure, the guy had hit him before, but never in that kind of way. The kind of way that means 'I wants you dead'.

"Dude, you are such a girl," Puck says, like ninety percent sure he's going to get himself into deeper shit. "Soft touching the face and shit? Come on, thought I taught you better man."

Finn – shockingly – does not respond with violence or personal attacks. He actually smiles a little, which makes Puck feel a little less like everything's gone to shit (which it kind of totally has). "Yeah, you're probably right. It would explain a lot. Still, you do well with chicks, right?"

Oh, great. They're back to that.

Puck wants to repeat his refusals from before, but they kind of refuse to come out – he thinks he can feel the wall in the back of his throat, tasting the way Finn's mouth did, all chocolate and cheap booze. Finn rolls his eyes and brings their mouths together again, and Puck actually gives in this time, if only because Finn can't kiss for shit (that's not it and it never has been, but whatever). He just rolls his eyes at Finn's clumsiness, bringing a hand to the back of his head and taking dominance of the kiss – surprisingly, given how pissed off he is, Finn lets him.

Finn pulls away after a few seconds. "Wow. You really are a whore."

And with that, Puck's stomach starts rolling again as Finn shoves him back down, and he lands on the couch with an 'oof' sound. "Dude–" Puck cuts off whatever he was going to say as Finn kneels down beside him, clumsily groping for Puck's dick. He finds it quickly (well, it wasn't exactly hidden) and it becomes apparent to both boys that, yeah, Puck's kind of hard. He kind of expects Finn to say something, mock him for this, but he doesn't. Thank God.

"Dude, I'm not sure we should..." Puck trails off. He doesn't know when _he_ started thinking about consequences, but what he knows is – this isn't right. Finn's doing this for all the wrong reasons, giving into the kinds of impulses guys like Finn _don't give into_ – that's what makes them guys like Finn, and not guys like Puck. Puck doesn't even know why he's going along with it, because deep down he knows if he does this he's just going to screw Finn over worse, but there's some dark part of his brain that doesn't care and just wants what it wants. Whatever that is.

He is so fucked up.

"God, shut _up," _Finn groans, catching Puck off-guard. "You've always talked too much, you know? Said so much bullshit I was practically drowning in it. I probably should have called you on all your shit forever ago, but no, I let it slide. Like I have let _every fucking thing_ slide for _twelve years_."

Puck winces as he looks at Finn's face; the expression that shows that he really didn't mean to say that last bit. Puck sort of wonders how much Finn _means_ to be doing any of this. It's that fact – Finn isn't in as much control of this as appears – that makes Puck realize something; that this is more of a necessity than anything. It'll break them both further and he knows it, but unless he does this, the simple fact is Finn will never be able to look at him again.

Puck just doesn't know how to exist without him (okay, gayest thing he has ever thought, _ever_, way gayer than the fact he is probably about to actually fuck a guy – shit), so he does have to do it. It makes him uncomfortable, and alerts some bit at the back of his brain – the bit reciting his mom's impromptu feminist speeches on how chicks should never be pressured into sex and whatever – but he doesn't listen to that, because he knows what he needs to do.

Finn's mouth parts slightly like he's about to say something, but he chooses against it, snapping his jaw shut as he pulls down the zipper of Puck's jeans.

Fuck.

Puck is about to panic. He can't panic.

Fuck fuck fuck.

He closes his eyes and takes in deep breaths, like those random doctors on daytime TV advise with stress, listening as he hears Finn's huge frame rustling and doing... stuff. Puck doesn't check want. He feels one of Finn's enormous hands close around his cock, stroking steadily, and Puck decides that is _it_. He is in too deep, there is no way out now.

The prospect is less terrifying than it probably should be.

Puck opens his eyes again, watching Finn, who discarded his jeans at some point – Puck can see his hard cock jutting out, and okay, that's a bit terrifying. Finn isn't paying much attention to himself, however, his face screwed up in intense concentration as he strokes Puck – he's a lot better at this than he was at kissing. Puck guesses that's not completely bizarre; there a very few teenage males in existence who don't actually stroke a dick on a regular basis, and that knowledge probably applies when it's someone else's. So whatever.

Finn tightens his grip and Puck bites back a ridiculously girly moan that just threatened to escape. Fuck no. Even it is a _guy_ he's fucking, and this whole thing is just Finn's really screwed up way of making him pay for his sins, Noah Puckerman is not a freaking girl. He does not moan. He doesn't even really want to be doing this.

He thinks.

Finn shuffles closer, running his thumb over the slit and Puck can't help but buck his hips up, further into Finn's hand. He really doesn't want to think about that. Then he notices what Finn is holding in his hand; condom and a bottle of lube.

Fuck. They are playing for real.

"Dude," Puck says, trying to speak through his badly-concealed nerves and the handjob, "I know I don't have great luck with these things, but I'm pretty sure neither of us is gonna get pregnant."

Finn rolls his eyes. "Yeah, whatever. Fucking a whore without a condom? Yeah, that's not a good way to get diseases and die."

Puck grimaces. "I'm not a whore."

Finn shrugs, tearing open the packet and letting go of Puck's cock – he tries not to make some kind of noise at the loss, because that would just be pathetic, and probably wouldn't support his "not a whore" argument to well. Finn holds the condom down, and it takes Puck a few seconds to realize that Finn is putting it on _him_, not himself. Not that he's complaining, but it's a little confusing.

"Finn?"

"What?" Finn looks annoyed. "I told you; if you're the fucking ride of the century, then I am taking my turn."

He sounds so angry and self-confident, but his hands are shaking, and he's completely failing to put the damn thing on. Puck lets out a shaky breath that is equal parts exasperation and relief – sure, Finn's awkwardness is making things more difficult than they need to be, but it's also pretty much his last reminder that this is still _Finn_, his best friend, and he has not been replaced by some kind of evil vengeful spirit (which, given the way Finn is acting, seemed like an increasingly plausible possibility).

"Dude, here, let me," he says, pretty much yanking the thing out of Finn's hand, looking away at the smirk he gets. He rolls it down onto himself, then looks back at Finn's face, as if daring him to say something.

Finn sucks in a deep breath. "Okay then," he says, and then he's reaching for the lube. Puck holds out a hand to grab it, but Finn swats him away.

"Fuck no," he growls. "You are not in control here, Puck; you're not even _participating_. You're a whore, you're barely more than a _toy_; you just get to lie there while I ride you and make myself come. Okay?"

Puck does his best not to groan – whether because that was really hot or really depressing, he's not sure. He watches as Finn pours a generous amount of the slick substance onto his fingers, some of it dripping down onto Puck's clothes – even when being scary and angry and shit, Finn hasn't stopped being a clumsy bastard. That's a bit of a comfort.

Finn draws those slicked up fingers back, under his shirt (why hasn't he taken that off yet?), easily sliding one inside himself. He grimaces a little, but doesn't hesitate, rocking his hips as Puck bites his lip. "Fuck," Finn says, jerking that finger around and exploring. He puts in a second, and Puck just kind of... watches, as his tight ass clenches around those fingers, and Puck can't help imagining the way it's going to feel in there. Finn's face is flushed red, biting his own lip gently, eyes half-closed and enjoying the sensations, lazy-good just like Puck imagined–

Puck didn't imagine anything. No freaking way.

Fuck.

Finn sticks a third finger in there, and Puck's got a weird feeling, like that probably shouldn't fit – have you _seen_ the size of Finn's hands? - but that's not the point, not when Finn is up there above him, fucking himself in preparation for Puck's cock. Okay, he doesn't know what the point _is_, but whatever.

"Finn," Puck is unable to stop that groan, even though it sounds a little too much like begging for his comfort. Fuck.

"Yeah," Finn murmurs, sounding a little less pissed, as if he's forgotten that it's _Puck_ he's doing this with, or at least he's forgotten that they kind of hate each other now.

Well, at least Finn hates him. Puck doesn't hate people without reason (okay, often his reasons aren't very good, but they are _reasons_).

"I'm ready," Finn eventually says, not bothering to ask if Puck is – not really a surprise. Then again, Puck's not the one who's going to have dick up his ass, so it would kind of make sense even if Finn didn't want to smash his brains open with a rock.

Finn squeezes some more lube onto his hand, efficiently coating Puck's cock with it. Then he grabs Puck's hips, shifting himself into position with the head of Puck's cock pressed against his hole, and he pauses. Puck kind of wants to ask him to stop, or wait, or _something_, and he doesn't know why.

He doesn't. What right does he have to ask anything, really?

This Finn just goes for it, sinking down, his ass clenching tight around Puck's cock. And he means _tight_. Puck tries really hard not to moan, but he doesn't quite manage it, because seriously, Puck's never felt this good in someone before; felt it this hot and ready and, to be slightly repetitive, _tight_ before. Sure, he slipped into Santana's backdoor a few times, and a few of his MILFs', but it was nothing like this.

(But that has nothing to with the fact this is Finn, and not just some cheap fucks. Puck doesn't know what it is, but that's not it.)

Finn sinks further down, face scrunching up like he's in pain as he goes as far as he can.

"Dude, you okay?" Puck asks.

"Shut up," Finn spits, a lot less composed than before. He pauses to take in a deep breath, then shuffles his hips a bit, and then... _something_ happens; something that makes Finn buck up and whimper.

Puck tries to think, and remembers his research right after Finn joined Glee and freaking lied about it; that stuff about prostates.

...Oh.

Finn sighs shakily, and raises himself back up, before slamming back onto Puck's cock with a moan. Puck wants to mock him for the girly noises, but it's not the place or time, and this isn't about him. This is about Finn, and making sure Finn will be able to look him in the eye ever again. Maybe like seventy percent of Puck doesn't think it'll really work, but fuck if he's gonna give up.

Plus, he's getting one of the tightest fucks _ever_ out of this, so it's not really like a massive gamble.

Finn's eyes roll back in his head and he starts moving properly; up and down clenching on Puck's cock, the look on his face making sure Puck knows how much he is loving this, even when he fucking hates it. Puck suddenly has one of those moments; the ones where you step back and go, _Wait, what the fuck am I doing?_

Puck considers this question. He's fucking his best friend's brains out because said best friend hates him for impregnated said best friend's girlfriend, and crazy hate sex seems to be the only way Finn will tolerate Puck being a presence in his life anymore, and Puck doesn't know what will happen if they _stop_ being part of each other's lives. They just haven't ever _not_ been part of each other's lives; Puck's never learned what not being the 'Puck' half of 'Finn-and-Puck' involves.

He's not doing this because he wants to. Because Finn's girlfriend could never be as good as the real deal. Because they've shared everything but this. Puck needs to believe that; that this is all Finn's revenge scenario, and not kind of what he's always wanted.

Fuckfuckfuckfuckfuck.

Finn's huge hands are pressing down his shoulders, digging his nails in, and Puck's sure he's going to leave scratchmarks and bruises. The fucking is great, but that just fucking stings. He kind of wants to say, _You're hurting me_, but he really doubts Finn is going to care, and besides, that would make him a total pussy. He can deal with a few bruises.

Finn's rhythm is speeding up, getting slightly more irregular (not that he was that steady to start with), and Puck realizes that Finn's getting close. Puck's getting close too, and _fuck_, because this can't end yet. When it ends, Puck's going to realize this didn't work, and Finn is still going to want him dead and everything's just going to suck worse. Puck can't deal with that yet.

But Finn is moaning in his ear (_And he says I'm the whore_, thinks Puck), and it's all too much; when Finn splatters onto his chest, ass clenching as he comes, it's too much and Puck gives in, shooting with a cry that sounds... less than joyful.

Finn rolls off quickly, grabbing his jeans off the floor. Puck is slowly, gradually pulling himself up on the couch, vaguely looking for where his clothes are.

"Dude–"

"I don't want to hear is," Finn cuts him off, doing up the zip of his jeans. "And getting some fucking clothes on."

Puck just rolls his eyes. "Given how much work you put into getting me out of those, I wouldn't be so quick to get me back in them."

And he's grinning cockily, like he always is, but it's not real. Because he knows, he _knows _it didn't work. Finn still hates him, and won't look at him, and they're not any better than they were before, They're probably even worse. Even if he managed to make Finn need a whore, he's _still_ the whore, and Finn is still better than him.

Not that he's really a whore, but right now, Finn kind of defines reality.

"Work. Right," Finn says, and he actually reaches for his wallet – Puck wants to be sick.

When Finn opens it, he pauses, and Puck stands to go see what the fuck he's looking at anyway. He feels even sicker when he realizes it's a picture of Quinn.

"It's funny," Finn says. "I always thought, if something like this happened... she'd be the one who'd really break my heart."

There is a painful pause where Puck tries to think of what the fuck he can say this time, but then Finn's face hardens again and he reaches into the wallet, tossing a whole bunch of cash out on the floor.

"There you go. After all, you've got a baby to support, best get all the money you can."

Then Finn storms off upstairs. Puck doesn't bother to go after him before leaving; he just shrugs a little, gets dressed, and collects the whore-money.


End file.
